JRE 8 rt.jar - com.* Package Source Code
JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries.
JRE (Java Runtime) 8 is the runtime environment included in JDK 8.
JRE 8 rt.jar libraries are divided into 6 packages:
com.* - Internal Oracle and Sun Microsystems libraries java.* - Standard Java API libraries. javax.* - Extended Java API libraries. jdk.* - JDK supporting libraries. org.* - Third party libraries. sun.* - Old libraries developed by Sun Microsystems.
JAR File Information:
Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
63,596,151 rt.jar
Here is the list of Java classes of the com.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.
✍: FYIcenter
⏎ com/sun/corba/se/impl/util/IdentityHashtable.java
/*
* Copyright (c) 1999, 2004, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
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/*
* Licensed Materials - Property of IBM
* RMI-IIOP v1.0
* Copyright IBM Corp. 1998 1999 All Rights Reserved
*
*/
package com.sun.corba.se.impl.util;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.NoSuchElementException;
/**
* IdentityHashtable is a modified copy of the 1.1.6 Hashtable class which
* does not rely on the hashCode() and equals() methods of the key or value;
* instead, it uses the System.identityHashcode() method and pointer comparison.
* In addition, all synchronization has been removed.
*/
public final class IdentityHashtable extends Dictionary {
/**
* The hash table data.
*/
private transient IdentityHashtableEntry table[];
/**
* The total number of entries in the hash table.
*/
private transient int count;
/**
* Rehashes the table when count exceeds this threshold.
*/
private int threshold;
/**
* The load factor for the hashtable.
*/
private float loadFactor;
/**
* Constructs a new, empty hashtable with the specified initial
* capacity and the specified load factor.
*
* @param initialCapacity the initial capacity of the hashtable.
* @param loadFactor a number between 0.0 and 1.0.
* @exception IllegalArgumentException if the initial capacity is less
* than or equal to zero, or if the load factor is less than
* or equal to zero.
* @since JDK1.0
*/
public IdentityHashtable(int initialCapacity, float loadFactor) {
if ((initialCapacity <= 0) || (loadFactor <= 0.0)) {
throw new IllegalArgumentException();
}
this.loadFactor = loadFactor;
table = new IdentityHashtableEntry[initialCapacity];
threshold = (int)(initialCapacity * loadFactor);
}
/**
* Constructs a new, empty hashtable with the specified initial capacity
* and default load factor.
*
* @param initialCapacity the initial capacity of the hashtable.
* @since JDK1.0
*/
public IdentityHashtable(int initialCapacity) {
this(initialCapacity, 0.75f);
}
/**
* Constructs a new, empty hashtable with a default capacity and load
* factor.
*
* @since JDK1.0
*/
public IdentityHashtable() {
this(101, 0.75f);
}
/**
* Returns the number of keys in this hashtable.
*
* @return the number of keys in this hashtable.
* @since JDK1.0
*/
public int size() {
return count;
}
/**
* Tests if this hashtable maps no keys to values.
*
* @return <code>true</code> if this hashtable maps no keys to values;
* <code>false</code> otherwise.
* @since JDK1.0
*/
public boolean isEmpty() {
return count == 0;
}
/**
* Returns an enumeration of the keys in this hashtable.
*
* @return an enumeration of the keys in this hashtable.
* @see java.util.Enumeration
* @see java.util.Hashtable#elements()
* @since JDK1.0
*/
public Enumeration keys() {
return new IdentityHashtableEnumerator(table, true);
}
/**
* Returns an enumeration of the values in this hashtable.
* Use the Enumeration methods on the returned object to fetch the elements
* sequentially.
*
* @return an enumeration of the values in this hashtable.
* @see java.util.Enumeration
* @see java.util.Hashtable#keys()
* @since JDK1.0
*/
public Enumeration elements() {
return new IdentityHashtableEnumerator(table, false);
}
/**
* Tests if some key maps into the specified value in this hashtable.
* This operation is more expensive than the <code>containsKey</code>
* method.
*
* @param value a value to search for.
* @return <code>true</code> if some key maps to the
* <code>value</code> argument in this hashtable;
* <code>false</code> otherwise.
* @exception NullPointerException if the value is <code>null</code>.
* @see java.util.Hashtable#containsKey(java.lang.Object)
* @since JDK1.0
*/
public boolean contains(Object value) {
if (value == null) {
throw new NullPointerException();
}
IdentityHashtableEntry tab[] = table;
for (int i = tab.length ; i-- > 0 ;) {
for (IdentityHashtableEntry e = tab[i] ; e != null ; e = e.next) {
if (e.value == value) {
return true;
}
}
}
return false;
}
/**
* Tests if the specified object is a key in this hashtable.
*
* @param key possible key.
* @return <code>true</code> if the specified object is a key in this
* hashtable; <code>false</code> otherwise.
* @see java.util.Hashtable#contains(java.lang.Object)
* @since JDK1.0
*/
public boolean containsKey(Object key) {
IdentityHashtableEntry tab[] = table;
int hash = System.identityHashCode(key);
int index = (hash & 0x7FFFFFFF) % tab.length;
for (IdentityHashtableEntry e = tab[index] ; e != null ; e = e.next) {
if ((e.hash == hash) && e.key == key) {
return true;
}
}
return false;
}
/**
* Returns the value to which the specified key is mapped in this hashtable.
*
* @param key a key in the hashtable.
* @return the value to which the key is mapped in this hashtable;
* <code>null</code> if the key is not mapped to any value in
* this hashtable.
* @see java.util.Hashtable#put(java.lang.Object, java.lang.Object)
* @since JDK1.0
*/
public Object get(Object key) {
IdentityHashtableEntry tab[] = table;
int hash = System.identityHashCode(key);
int index = (hash & 0x7FFFFFFF) % tab.length;
for (IdentityHashtableEntry e = tab[index] ; e != null ; e = e.next) {
if ((e.hash == hash) && e.key == key) {
return e.value;
}
}
return null;
}
/**
* Rehashes the contents of the hashtable into a hashtable with a
* larger capacity. This method is called automatically when the
* number of keys in the hashtable exceeds this hashtable's capacity
* and load factor.
*
* @since JDK1.0
*/
protected void rehash() {
int oldCapacity = table.length;
IdentityHashtableEntry oldTable[] = table;
int newCapacity = oldCapacity * 2 + 1;
IdentityHashtableEntry newTable[] = new IdentityHashtableEntry[newCapacity];
threshold = (int)(newCapacity * loadFactor);
table = newTable;
//System.out.println("rehash old=" + oldCapacity + ", new=" + newCapacity + ", thresh=" + threshold + ", count=" + count);
for (int i = oldCapacity ; i-- > 0 ;) {
for (IdentityHashtableEntry old = oldTable[i] ; old != null ; ) {
IdentityHashtableEntry e = old;
old = old.next;
int index = (e.hash & 0x7FFFFFFF) % newCapacity;
e.next = newTable[index];
newTable[index] = e;
}
}
}
/**
* Maps the specified <code>key</code> to the specified
* <code>value</code> in this hashtable. Neither the key nor the
* value can be <code>null</code>.
* <p>
* The value can be retrieved by calling the <code>get</code> method
* with a key that is equal to the original key.
*
* @param key the hashtable key.
* @param value the value.
* @return the previous value of the specified key in this hashtable,
* or <code>null</code> if it did not have one.
* @exception NullPointerException if the key or value is
* <code>null</code>.
* @see java.util.Hashtable#get(java.lang.Object)
* @since JDK1.0
*/
public Object put(Object key, Object value) {
// Make sure the value is not null
if (value == null) {
throw new NullPointerException();
}
// Makes sure the key is not already in the hashtable.
IdentityHashtableEntry tab[] = table;
int hash = System.identityHashCode(key);
int index = (hash & 0x7FFFFFFF) % tab.length;
for (IdentityHashtableEntry e = tab[index] ; e != null ; e = e.next) {
if ((e.hash == hash) && e.key == key) {
Object old = e.value;
e.value = value;
return old;
}
}
if (count >= threshold) {
// Rehash the table if the threshold is exceeded
rehash();
return put(key, value);
}
// Creates the new entry.
IdentityHashtableEntry e = new IdentityHashtableEntry();
e.hash = hash;
e.key = key;
e.value = value;
e.next = tab[index];
tab[index] = e;
count++;
return null;
}
/**
* Removes the key (and its corresponding value) from this
* hashtable. This method does nothing if the key is not in the hashtable.
*
* @param key the key that needs to be removed.
* @return the value to which the key had been mapped in this hashtable,
* or <code>null</code> if the key did not have a mapping.
* @since JDK1.0
*/
public Object remove(Object key) {
IdentityHashtableEntry tab[] = table;
int hash = System.identityHashCode(key);
int index = (hash & 0x7FFFFFFF) % tab.length;
for (IdentityHashtableEntry e = tab[index], prev = null ; e != null ; prev = e, e = e.next) {
if ((e.hash == hash) && e.key == key) {
if (prev != null) {
prev.next = e.next;
} else {
tab[index] = e.next;
}
count--;
return e.value;
}
}
return null;
}
/**
* Clears this hashtable so that it contains no keys.
*
* @since JDK1.0
*/
public void clear() {
IdentityHashtableEntry tab[] = table;
for (int index = tab.length; --index >= 0; )
tab[index] = null;
count = 0;
}
/**
* Returns a rather long string representation of this hashtable.
*
* @return a string representation of this hashtable.
* @since JDK1.0
*/
public String toString() {
int max = size() - 1;
StringBuffer buf = new StringBuffer();
Enumeration k = keys();
Enumeration e = elements();
buf.append("{");
for (int i = 0; i <= max; i++) {
String s1 = k.nextElement().toString();
String s2 = e.nextElement().toString();
buf.append(s1 + "=" + s2);
if (i < max) {
buf.append(", ");
}
}
buf.append("}");
return buf.toString();
}
}
⏎ com/sun/corba/se/impl/util/IdentityHashtable.java
Or download all of them as a single archive file:
File name: jre-rt-com-1.8.0_191-src.zip File size: 8099783 bytes Release date: 2018-10-28 Download
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